A liquid crystal display is constituted of a liquid crystal cell in which transparent electrodes, a liquid crystal layer, and a color filter is sandwiched by glass plates, and two polarizing plates provided on both sides thereof. Each polarizing plate has a structure in which a polarizer (also referred to as a polarizer or a polarizing film) is sandwiched by two polarizing plate protective films.
As this polarizing plate protective film, a cellulose ester film of which retardation value is easily adjusted is usually used.
According to the expansion of the field of liquid crystal displays, the deterioration due to fading caused by the moisture absorption of the polarizer has become a problem, and the polarizing plate has been asked for higher moisture resistance as the utilization field of a liquid crystal display expands.
Since the moisture resistance of a conventionally used cellulose ester film is limited, there has been proposed a technique to use an acrylic resin which is a material for a low moisture absorbing acrylic film, for example, polymethylmethacrylate copolymer, is used for polarizing plate protective films on both sides (refer to Patent Document 1).
However, a polarizing plate having an acrylic film as a polarizing plate protective film is inferior with respect to brittleness, therefore, it suffers from poor workability, for example, a cutting property. Accordingly, there has been proposed after that a technique to uses a polycycloorefine film, a polycarbonate film or a polyester film as a polarizing plate protective film facing the external environment, and a cellulose ester film as a polarizing plate protective film facing the liquid crystal cell (refer to Patent Documents 2 and 3).
However, even when the above mentioned low moisture absorbing polymer film was used as a polarizing plate protective film facing the external environment, fading deterioration of a polarizer due to water was sometimes observed.